COA2021 consists of several tracks, including, but not limited to, the following specific topics:

I. Underwater acoustics and acoustical oceanography

1.1 Sonar and transducers

1.2 Sound propagation and scattering

1.3 Acoustical oceanography

1.4 Geoacoustic inversion

1.5 Bioacoustics

1.6 Seismo-acoustics

1.7 Signal coherence and fluctuation

1.8 Air / sea interaction acoustics

1.9 Modeling techniques for underwater acoustic scattering and propagation 

II. Ocean acoustic observatories and ocean acoustic instruments, systems and platforms

2.1 Oceanographic acoustic instrumentation and sensors

2.2 Calibration of acoustic systems and metrology

2.3 Acoustic systems design, navigation, performance of AUV, MUV, ROV

2.4 Buoy technology

2.5 Design of new experimental facilities to address future problems in underwater acoustics

III. Ocean sound propagation modeling and experiments

3.1 Sound propagation in shallow and deep water

3.2 Non-linear acoustic field modeling and analysis

3.3 Sound field fluctuations in the ocean

3.4 Statistic properties of ocean sound field

3.5 Three-dimensional sound propagation modeling

IV. Marine sediment acoustics

4.1 Multibeam echo sounding: Bathymetry and sediment classification

4.2 Geoacoustic parameters inversion

4.3 Acoustic properties of marine sediments: modeling and measuring

4.4 Gas effects and detection in marine sediments

V. Ocean noise and reverberation

5.1 Acoustic Monitoring of Ocean Environments and Processes: Biology, Ecology, Geophysics and Man-made activities

5.2 Underwater Noise - Modelling and Measurements

5.3 Underwater structural vibration and noise radiation

5.4 Novel material and device for underwater noise control

5.5 Methodology of underwater noise data processing

5.6 Ocean reverberation – models and data

VI. Underwater acoustic communication and networking

6.1 Underwater Acoustic Communication

6.2 Marine Mammal Acoustics and bionics

VII. Signal processing: Sonar modeling, signal detection and estimation, target tracking and recognition

7.1 Sonar signal processing

7.2 Array signal processing

7.3 Model-based signal processing techniques

7.4 Vector sensor processing

7.5 Synthetic aperture sonar (active and passive)

7.6 Object classification and pattern recognition (parametric and non-parametric)

7.7 Sonar imaging processing

7.8 Acoustic telemetry and communication

7.9 Biologically inspired processing

7.10 Large Time-Bandwidth acoustic signals for target detection and tracking

7.11 Machine learning, compressive sensing and signal processing

7.12 Neural networks and info processing

VIII. Design, development, testing and calibrations for acoustical sensor and array

8.1 Vector hydrophone research

8.2 Wideband transducer

IX. Polar acoustics and under-ice propagation

9.1 Waveguide propagation in Arctic sea ice

9.2 Ambient noise of Arctic sea

9.3 Under-ice communication and acoustic signal processing

9.4 Under-ice acoustical experimentation

9.5 Other Polar acoustical related studies

X. Underwater non-acoustic detection and communication

10.1 Marine optics technology and optical sensors

10.2 Underwater Wireless Optical Communication

10.3 E-M sensing

10.4 Magneto Inductive Communication for UWSN

10.5 Multi-sensing technology fusion and measurement

XI. Underwater acoustics in extreme and special environments: discovery, observation and application

11.1 Applications and Observations related with Oceanic front, thermocline, vortex, water mass

11.2 Propagation, channel and noise background characteristics in very shallow water

11.3 Expedition and discovery for the endeavor with the acoustics

11.4 Acoustic characteristics in estuary, mixed-zone, monsoon season , and other period or location with special acoustic feature or phenomenon